1. Technical Field
The present invention relates to a liquid crystal device and a projector.
2. Related Art
Projectors have come into widespread use in homes. Accordingly, a spatial light modulation device of a projector having low cost, long life span and capable of producing images of high brightness is desired to be obtained. A representative example of the spatial light modulation device is a liquid crystal device. A known example of a liquid crystal display is an active matrix type liquid crystal device having thin-film transistors TFTs as pixel switching elements. In this liquid crystal device, when light is irradiated onto a channel region of the TFT provided in each of a plurality of pixels provided in the liquid crystal device, a light leakage current occurs due to excitation by the light and thus the characteristics of the TFT are changed. Accordingly, the TFTs are protected by light-shielding films provided on a TFT array substrate and an opposite substrate (see, for example, JP-A-2-64690).
Generally, in the liquid crystal device mounted in the projector, the opposite substrate on which the TFTs are not formed is disposed toward a light source. The light-shielding film of the opposite substrate blocks the light emitted from the light source and prevents the light from directly entering the TFTs provided at the opposite side thereof. The light-shielding film provided on the TFT array substrate prevents returning light from entering the rear surface of the TFTs. Accordingly, the TFTs are doubly protected.
Since such light-shielding films can be seen as thin black lines in regions between the projected pixels, surface roughness is increased and thus display quality deteriorates when displaying a moving image. Since the TFTs are shielded from light by the light-shielding film provided doubly, it can be difficult to obtain sufficient brightness. This tendency is more pronounced in an image formed by rows of pixels each having a small size in recent devices due to progress of manufacturing technology, compared with other existing devices in which the size of the pixel is sufficiently large compared with that of the light-shielding film.